47. GREAT-BLACK-BACKED GULL. 

 Larus marinus. 



LONG-WINGED SWIMMERS 



Range. North Atlantic on both the American 

 and European sides; breeds from Nova Scotia 

 northward and winters south to the Great Lakes 

 and the Middle States. 



The largest of the Gulls (thirty inches long) 

 and unlike any other. The mantle is dark slaty 

 black, and the primaries are black with white 

 tips. The bill is very large and powerful and 



m 



Great Black-backed Gull 

 Kumlien's Gull 



Grayish buff 



quite strongly hooked. They are quite abundant 

 birds in their range, and are very quarrelsome, 

 both among themselves and other species. They 

 do not breed in as large colonies as do the other 

 Gulls, half a dozen pairs appropriating a small 

 island to the exclusion of all other birds. They 

 are very rapacious birds and live to a great ex- 

 tent, especially during the breeding season, upon the eggs and young of other 

 birds such as Ducks, Murres and smaller Gulls. They place their nests upon 

 the higher portions of sandy islands. They are made of grasses and seaweed. 

 The three eggs are laid early in June; they are grayish or brownish, spotted 

 with brown and lilac. Size 3x2.15. Data.- -South Labrador, June 21, 1884. 

 Three eggs. Nest on a small island off the coast; of grasses and moss. 



18. SLATY-BACKED GULL. Larus schistisagus. 



Range. North Pacific and Arctic Oceans. 



This Gull, which is similar to the Great Black-backed, but is smaller and has 

 a lighter mantle, does not breed in any considerable numbers on the Ameri- 

 can side of the Pacific. It nests in June on some of the islands in Bering Sea 

 and probably more commonly farther onrth. They often nest in company with 

 other species, placing their small mounds of seaweed on the ground on the 

 higher parts of the islands. The full set contains three eggs of grayish or 

 brownish color, spotted with dark brown or black. Size 2.90 x 2. Data. Har- 

 rowby Bay, N. W. T. Canada, June 11, 1901. Nest of grass, roots and mud and 

 lined with dry grass; on point making into the bay. Collector, Capt. H. H. 

 Bodfish. 



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